/Engine/Plugins/Runtime/GameplayAbilities/Source/GameplayAbilities/Public/AbilitySystemComponent.h
Applies an inplace mod to the given attribute. Unlike ApplyModToAttribute this function will run on the client or server. This may result in problems related to prediction and will not roll back properly.
void ApplyModToAttributeUnsafe ( const [FGameplayAttribute](API\Plugins\GameplayAbilities\FGameplayAttribute) & Attribute, [TEnumAsByte](API\Runtime\Core\Containers\TEnumAsByte)< [EGameplayModOp::Type](API\Plugins\GameplayAbilities\EGameplayModOp__Type) > ModifierOp, float ModifierMagnitude )